Core/Spells: Apply spell modifiers multiple times to each cast, based on number of matched SpellFamilyFlags bits

5 files changed, 43 insertions, 30 deletions

diff --git a/src/server/game/Entities/Player/Player.cpp b/src/server/game/Entities/Player/Player.cpp
index cf8d7b08a6c..a8fe32ceb74 100644
--- a/src/server/game/Entities/Player/Player.cpp
+++ b/src/server/game/Entities/Player/Player.cpp
@@ -22403,45 +22403,45 @@ void Player::SendRemoveControlBar() const
     SendDirectMessage(packet.Write());
 }
 
-bool Player::IsAffectedBySpellmod(SpellInfo const* spellInfo, SpellModifier const* mod, Spell* spell)
+uint32 Player::IsAffectedBySpellmod(SpellInfo const* spellInfo, SpellModifier const* mod, Spell const* spell)
 {
     if (!mod || !spellInfo)
-        return false;
+        return 0;
 
     // First time this aura applies a mod to us and is out of charges
-    if (spell && mod->ownerAura->IsUsingCharges() && !mod->ownerAura->GetCharges() && !spell->m_appliedMods.count(mod->ownerAura))
-        return false;
+    if (spell && mod->ownerAura->IsUsingCharges() && !mod->ownerAura->GetCharges() && !spell->m_appliedMods.contains(mod->ownerAura))
+        return 0;
 
     switch (mod->op)
     {
         case SpellModOp::Duration: // +duration to infinite duration spells making them limited
             if (spellInfo->GetDuration() == -1)
-                return false;
+                return 0;
             break;
         case SpellModOp::CritChance: // mod crit to spells that can't crit
             if (!spellInfo->HasAttribute(SPELL_ATTR0_CU_CAN_CRIT))
-                return false;
+                return 0;
             break;
         case SpellModOp::PointsIndex0: // check if spell has any effect at that index
         case SpellModOp::Points:
             if (spellInfo->GetEffects().size() <= EFFECT_0)
-                return false;
+                return 0;
             break;
         case SpellModOp::PointsIndex1: // check if spell has any effect at that index
             if (spellInfo->GetEffects().size() <= EFFECT_1)
-                return false;
+                return 0;
             break;
         case SpellModOp::PointsIndex2: // check if spell has any effect at that index
             if (spellInfo->GetEffects().size() <= EFFECT_2)
-                return false;
+                return 0;
             break;
         case SpellModOp::PointsIndex3: // check if spell has any effect at that index
             if (spellInfo->GetEffects().size() <= EFFECT_3)
-                return false;
+                return 0;
             break;
         case SpellModOp::PointsIndex4: // check if spell has any effect at that index
             if (spellInfo->GetEffects().size() <= EFFECT_4)
-                return false;
+                return 0;
             break;
         default:
             break;
@@ -22458,6 +22458,9 @@ void Player::GetSpellModValues(SpellInfo const* spellInfo, SpellModOp op, Spell*
     *flat = 0;
     *pct = 1.0f;
 
+    if (!spellInfo->IsAffectedBySpellMods())
+        return;
+
     auto spellModOpBegin = std::ranges::lower_bound(m_spellMods, op, std::ranges::less(), &SpellModifier::op);
     if (spellModOpBegin == m_spellMods.end() || (*spellModOpBegin)->op != op)
         return;
@@ -22587,33 +22590,36 @@ void Player::GetSpellModValues(SpellInfo const* spellInfo, SpellModOp op, Spell*
 
     for (SpellModifier* mod : spellModTypeRange(SPELLMOD_FLAT))
     {
-        if (!IsAffectedBySpellmod(spellInfo, mod, spell))
+        uint32 applyCount = IsAffectedBySpellmod(spellInfo, mod, spell);
+        if (!applyCount)
             continue;
 
         int32 value = static_cast<SpellModifierByClassMask*>(mod)->value;
         if (value == 0)
             continue;
 
-        *flat += value;
+        *flat += value * applyCount;
         Player::ApplyModToSpell(mod, spell);
     }
 
     for (SpellModifier* mod : spellModTypeRange(SPELLMOD_LABEL_FLAT))
     {
-        if (!IsAffectedBySpellmod(spellInfo, mod, spell))
+        uint32 applyCount = IsAffectedBySpellmod(spellInfo, mod, spell);
+        if (!applyCount)
             continue;
 
         int32 value = static_cast<SpellFlatModifierByLabel*>(mod)->value.ModifierValue;
         if (value == 0)
             continue;
 
-        *flat += value;
+        *flat += value * applyCount;
         Player::ApplyModToSpell(mod, spell);
     }
 
     for (SpellModifier* mod : spellModTypeRange(SPELLMOD_PCT))
     {
-        if (!IsAffectedBySpellmod(spellInfo, mod, spell))
+        uint32 applyCount = IsAffectedBySpellmod(spellInfo, mod, spell);
+        if (!applyCount)
             continue;
 
         // skip percent mods for null basevalue (most important for spell mods with charges)
@@ -22631,13 +22637,14 @@ void Player::GetSpellModValues(SpellInfo const* spellInfo, SpellModOp op, Spell*
                 continue;
         }
 
-        *pct *= 1.0f + CalculatePct(1.0f, value);
+        *pct *= std::pow(1.0f + CalculatePct(1.0f, value), applyCount);
         Player::ApplyModToSpell(mod, spell);
     }
 
     for (SpellModifier* mod : spellModTypeRange(SPELLMOD_LABEL_PCT))
     {
-        if (!IsAffectedBySpellmod(spellInfo, mod, spell))
+        uint32 applyCount = IsAffectedBySpellmod(spellInfo, mod, spell);
+        if (!applyCount)
             continue;
 
         // skip percent mods for null basevalue (most important for spell mods with charges)
@@ -22655,7 +22662,7 @@ void Player::GetSpellModValues(SpellInfo const* spellInfo, SpellModOp op, Spell*
                 continue;
         }
 
-        *pct *= value;
+        *pct *= std::pow(value, applyCount);
         Player::ApplyModToSpell(mod, spell);
     }
 }
diff --git a/src/server/game/Entities/Player/Player.h b/src/server/game/Entities/Player/Player.h
index 36bf7c764eb..ae955a9b683 100644
--- a/src/server/game/Entities/Player/Player.h
+++ b/src/server/game/Entities/Player/Player.h
@@ -1993,7 +1993,7 @@ class TC_GAME_API Player final : public Unit, public GridObject<Player>
         PlayerSpellMap      & GetSpellMap()       { return m_spells; }
 
         void AddSpellMod(SpellModifier* mod, bool apply);
-        static bool IsAffectedBySpellmod(SpellInfo const* spellInfo, SpellModifier const* mod, Spell* spell = nullptr);
+        static uint32 IsAffectedBySpellmod(SpellInfo const* spellInfo, SpellModifier const* mod, Spell const* spell = nullptr);
         template <class T>
         void GetSpellModValues(SpellInfo const* spellInfo, SpellModOp op, Spell* spell, T base, int32* flat, float* pct) const;
         template <class T>
diff --git a/src/server/game/Spells/Auras/SpellAuraEffects.cpp b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
index 4d2749f28e3..36d3c91e33d 100644
--- a/src/server/game/Spells/Auras/SpellAuraEffects.cpp
+++ b/src/server/game/Spells/Auras/SpellAuraEffects.cpp
@@ -1203,7 +1203,7 @@ void AuraEffect::ApplySpellMod(Unit* target, bool apply, AuraEffect const* trigg
         // only passive and permament auras-active auras should have amount set on spellcast and not be affected
         // if aura is cast by others, it will not be affected
         if ((!aura->IsPassive() && !aura->IsPermanent() && !GetSpellInfo()->IsUpdatingTemporaryAuraValuesBySpellMod())
-            || aura->GetCasterGUID() != guid || !aura->GetSpellInfo()->IsAffectedBySpellMod(m_spellmod))
+            || aura->GetCasterGUID() != guid || !aura->GetSpellInfo()->IsAffectedBySpellMods() || !aura->GetSpellInfo()->IsAffectedBySpellMod(m_spellmod))
             continue;
 
         if (recalculateEffectIndex)
diff --git a/src/server/game/Spells/SpellInfo.cpp b/src/server/game/Spells/SpellInfo.cpp
index 5cadd602089..95432f8f02c 100644
--- a/src/server/game/Spells/SpellInfo.cpp
+++ b/src/server/game/Spells/SpellInfo.cpp
@@ -37,6 +37,7 @@
 #include "SpellMgr.h"
 #include "Vehicle.h"
 #include <G3D/g3dmath.h>
+#include <bit>
 
 uint32 GetTargetFlagMask(SpellTargetObjectTypes objType)
 {
@@ -1892,11 +1893,8 @@ bool SpellInfo::IsAffectedBySpellMods() const
     return !HasAttribute(SPELL_ATTR3_IGNORE_CASTER_MODIFIERS);
 }
 
-bool SpellInfo::IsAffectedBySpellMod(SpellModifier const* mod) const
+uint32 SpellInfo::IsAffectedBySpellMod(SpellModifier const* mod) const
 {
-    if (!IsAffectedBySpellMods())
-        return false;
-
     SpellInfo const* affectSpell = sSpellMgr->GetSpellInfo(mod->spellId, Difficulty);
     if (!affectSpell)
         return false;
@@ -1905,13 +1903,21 @@ bool SpellInfo::IsAffectedBySpellMod(SpellModifier const* mod) const
     {
         case SPELLMOD_FLAT:
         case SPELLMOD_PCT:
+        {
             // TEMP: dont use IsAffected - !familyName and !familyFlags are not valid options for spell mods
             // TODO: investigate if the !familyName and !familyFlags conditions are even valid for all other (nonmod) uses of SpellInfo::IsAffected
-            return affectSpell->SpellFamilyName == SpellFamilyName && static_cast<SpellModifierByClassMask const*>(mod)->mask & SpellFamilyFlags;
+            if (affectSpell->SpellFamilyName != SpellFamilyName)
+                return false;
+
+            // spell modifiers should apply as many times as number of matched SpellFamilyFlags bits (verified with spell 1218116 with modifier 384451 in patch 11.1.0 and client tooltip code since at least 3.3.5)
+            // unknown if this is a bug or strange design choice...
+            FlagsArray<uint32, 4> matched = static_cast<SpellModifierByClassMask const*>(mod)->mask & SpellFamilyFlags;
+            return std::popcount(matched[0]) + std::popcount(matched[1]) + std::popcount(matched[2]) + std::popcount(matched[3]);
+        }
         case SPELLMOD_LABEL_FLAT:
-            return HasLabel(static_cast<SpellFlatModifierByLabel const*>(mod)->value.LabelID);
+            return HasLabel(static_cast<SpellFlatModifierByLabel const*>(mod)->value.LabelID) ? 1 : 0;
         case SPELLMOD_LABEL_PCT:
-            return HasLabel(static_cast<SpellPctModifierByLabel const*>(mod)->value.LabelID);
+            return HasLabel(static_cast<SpellPctModifierByLabel const*>(mod)->value.LabelID) ? 1 : 0;
         default:
             break;
     }
@@ -5013,5 +5019,5 @@ bool SpellInfo::MeetsFutureSpellPlayerCondition(Player const* player) const
 
 bool SpellInfo::HasLabel(uint32 labelId) const
 {
-    return Labels.find(labelId) != Labels.end();
+    return Labels.contains(labelId);
 }
diff --git a/src/server/game/Spells/SpellInfo.h b/src/server/game/Spells/SpellInfo.h
index 0b5b168a9d5..f1e01769316 100644
--- a/src/server/game/Spells/SpellInfo.h
+++ b/src/server/game/Spells/SpellInfo.h
@@ -516,7 +516,7 @@ class TC_GAME_API SpellInfo
         bool IsAffected(uint32 familyName, flag128 const& familyFlags) const;
 
         bool IsAffectedBySpellMods() const;
-        bool IsAffectedBySpellMod(SpellModifier const* mod) const;
+        uint32 IsAffectedBySpellMod(SpellModifier const* mod) const;
         bool IsUpdatingTemporaryAuraValuesBySpellMod() const;
 
         bool CanPierceImmuneAura(SpellInfo const* auraSpellInfo) const;